Researchers in Antwerp have identified a strange white marking on the surface of Edvard Munch’sThe Scream as candle wax, disproving previous reports that the mark was a bird dropping resulting from the artist’s frequent practice of painting outside. “Munch employed a cardboard substrate to paint the Scream, a material that is particularly fragile and hygroscopic and would have suffered severe damage when left outdoors,” a spokesperson said.